Firearm.



PATENTED FEB. 28, 1905.

P. K. YOUNG & J. E. SHERIFF.

FIREARM.

APPLICATION FILED MAR. 2a, was

12 SHEETS-$55221 L N0. 783,770. PATENTED FEB.28,1905. F. K. YOUNG & J. E. SHERIFF. FIREARM.

APPLICATION FILED munze, was.

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FIREARM.

APPLICATION FILED MAR. 2a, 1903.

12 SHEETS-SEES! Q $5 ma QM w 2 N 3 3 wwi mnesw W (L. B MM mag-M No. '?83,'7'70. fiATENTED FEB. 28, 1905. P. K. YOUNG & J. E. SHERIFF.

FIREARM.

APPLIUATION FILED MA1L28,1903x No. 783,770. IPATENTED FEB. 28, 1905. P. K. YOUNG & J. E. SHERIFF.

FIREARM.

APPLICATION FILED MAR.29,1903x 12 BHBETSSHEIBT 6.

PATENTBD FEB. 28, 1905. F. K. YOUNG & J. E. SHERIFF.

FIREARM.

APPLICATION 21mm 1112. 2a, 1903.

12 SHEETS-SHEET 1.

l/ c'i nesses PATENTED FEB. 28, 1905.

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FIREARM.

APPLICATION FILE-D MAB. 28,1903.

F. K. YOUNG & J. B. SHERIFF.

min/eases QM; CL @QW No. 788,770. PATBNTED FEB. 28, 1905. F. K. YOUNG & J. E. SHERIFF.

FIREARM.

APPLIOATION FILED MAB. as. 1903.

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I21) 8 12/69 rs J M- No. 783,770. PATBNTED FEB. 28, 1905. P. K. YOUNG in J. E. SHERIFF.

FIREARM.

APPLICATION FILED MAB..2B,19OJ.

12 SHBETSSHEBT 10 14.; 1 J68 Zl/itnegses:

M 179.0514. fwda K7 7 No. 783,770. PATENTBD FEB. 28, 1905.

F. K, YOUNG & J. B. SHERIFF. FIREARM.

AFPL OATION FILED um. 29, 1903.

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mt nesses: fizventors:

UNITED STATES Patented February 28, 1905.

PATENT OFFICE.

FRANKLIN K. YOUNG, OF BOSTON, MASSACHUSETTS, AND JAM ES 1). SHER- IFF, OF BROOKLYN, NEW YORK, 'ASSlGNORS TO AMERICAN AU'lOMA'lK. ARMS COMPANY, OF SAUO, MAINE, A CORPORATION OF MAINE.

FIREARNL.

SPECIFICATION forming part of Letters Patent No. '7 B3,770, dated February 28, 1965. Application filed Match 2B, 1933. Sorial lie. 149,946.

To allwi'wm, it may concern:

Be it known that we, FRANKLIN K. YOUNG,

residing at Boston, county of Suffolk, State of;

Massachusetts, and J AMES E. SHERIFF, resid- 5 ing at Brooklyn, New York city, in the count-,3 of Kings and State of NewYork, citizens of the UnitedStates, have invented certain new and useful Improvements in Firearms, of which the following is a specification.

One object of the invention is to provide but the trigger will have to be released and again pulled before the second cartridge can be fired, and by pulling the trigger back a certain fartherdistance and holding it back all the cartridges in the magazine will be fired in rapid succession without further manipulation or movement of the trigger. Another object of the invention is to pro- 2 5 vide mechanism by which after the explosion the rearward movement of a sliding member or secondary bolt which carries the firing-pin unlocks the bolt. For convenience of description the secondary boltis termed the weight and will be hereinafter so called. The weight travels a certain distance before it unlocks the bolt in order to give 'time for 'the projectile to move some distance before the bolt becomes unlocked.

Another feature of the invention relates to the mechanism for locking the bolt after each forward movement of the bolt between firings.

Another feature of the invention relates to the mechanism for actuating the weight.

Another feature of the invention relates to 7 other features of the invention will be hereinnfter set forth.

The bolt has a partially rotary as well as a 5 sliding movement,-thcre being a rotary or turning movement in ;one direction to unlock the bolt aftcra discharge before it can more rcerwordly and aturning movement in the reverso direction to again lock the bolt at tho 5 5 end of it forward movement. In its rearward movemont it telescopes into tho bolt-case. The bolt is locked by means of lateral projections' which engage with notches in the side of the frame. v The weight has a sliding, but not. rotary, movcment., lt has a. sliding movement within theboltindepcndcntof the bolt, as well as a sliding. movement with the bolt. It has an initial rearward movement before the bolt moves. During its rearward 5 movement it engages with spiral projections on the intcriorof the bolt to rotate the bolt and partially, unlock it, the completion of the rotary movement and of the unlocking being produced by'engagemcnt of the bolt 7 with a cam-faceon the frame. -Aftcr tho bolt is unlocked it moves renrwardly, and

the weight also continues to more rem-ward l v. The rearward movement compresses the air in the air-cylinder, which after compression throws the bolt, weight, and firing-pin forward. A spring in the air-cylinder aids in driving the bolt forward. On the forward movement the bolt is turned in part by the rcverse engagement of the lever on the bolt with o the cam-face on the frame, and the completion of the turning is caused by engagement of a cam nttachment on the bolt with a cam nttnclv ment on the weight. The firing-pin has a sliding but not a rotary movement. lt'hns n 5 sliding movement within the weight independent of the weight, as well, as a sliding movement with the weight. The forwnrd end of the weight is engaged by a plunger which has a'limited movement in the head of the bolt. 9 The plunger is actuated rcarwardly by the rearward movement of a piston in the head of the cartridge when a cartridge is fired. The rearward movement of the plu ngrr issuddcnly side elevation, of the firing-pin.

checked by a stop on the bolt, and the impulse given to the weight causes the weight to con' tinue its rearward movement. The scar has a compound movement, being composed of two members secured together by a vertical pivot, and one of the members is mounted on a horizontal pivot in such manner that the entire sear has a vertically-rocking movement on the horizontal pivot and the rearward member has a laterally-turning movement on the vertical pivot. The rocking movement causes the sear to release the tiring-pin when the trigger is pulled. The horizontal movement on the vertical pivot is given to it by the peculiar form of the trigger when the trigger is pulled back into the automatic or full-back position, thereby throwing the sear into position where it will still engage the firing-pin on its forward rebound and compress the firing-pin spring; but it is in position where it engages an inclined surface on a fixed part of the weight in such manner as to depress the sear, so that as soon as the firing-pin spring is compressed to operative tension the sear will be released from engagement with the firing-pin and allow the firing-pin to be driven forward without again pulling the trigger.

The invention will now be fully described by reference to the accompanying drawings, and the several novel features will be particularly pointed out in the claims at the close of the specification.

Figurel is aside elevation of the breech portion of agun embodying the invention. Fig. 2 is a detail side elevation of the frame, showing the ejector in position to eject an empty shelL;

Fig. 3 is a rear end elevation of Fig. 2. Fig. 4 is a central longitudinal section with the parts in their normal position ready for firing and showing one cartridge in the chamber and the magazine empty, the position of the trigger when pulled into the semi-automatic position being shown in dotted lines. Fig. 5 is a plan section of the frame,showing the trigger mechanism and ejector in position. Fig. 6 is a front elevation of a portion of the trigger mechanism, tumbler, and sear assembled, showing the cam-faces thereon. Fig. 7 is a horizontal section on line 77 of Fig. 1. Fig. 8 is a rear elevation, and Fig. 9 is a side elevation, of a springwhich forms a cushion for the weight. Fig. 10 is a rear elevation, and Fig. 11 is a Fig. 12 is a section similar to Fig. 4 with the parts inthe position after the trigger has been pulled and cartridge exploded and the weight partially thrown back and the lugs about to engage the spiral projections on the interior of the bolt. In this section and in the following similar section there are shown four cartridges in the magazine. Fig. 12 is a detail section showing the trigger pulled part way back into the semi-automatic position. Fig. 13 isasection similar to Fig. 12 after the lugs have traversed the spirals and have cu hioned against the spring. the bolt being turned the amount of the spiral projections. Fig. 13 is a detail section showing the trigger engaged with the pivot 165 on the frame and pushed forward to disengage the trigger and the block to which it is pivoted and the air-cylinder partly withdrawn. Fig. 14 is a section similar to Fig. 13 after the bolt-handle has traversed the cam on the frame and the bolt is entirely unlocked. Fig. 15 is a section similar to Fig. 14 just as the rear end of the weight has struck the spiral compression-spring at the rear end of the casing. Fig. 16 is a section similar to Fig 15, the weight having completed its rearward movement, compressing the spring behind it, and the bolt telescoped onto the weight, the empty shell having been thrown out by its rear end. striking the ejector. Fig. 17 is asection on line 17 17 of Fig. 1. Fig. 18 is a section on line 18 18 of Fig. 1 after the bolt hasbcen entirely unlocked, as in Fig. 14, and showing in dotted lines the full complement of cartridges in the maga- Zine. Fig. 19 is a rear elevation, and Fig. 20 is a side elevation, of the weight. Fig. 21 is a section on line 21 21 of Fig. 20. Fig. 22 is a detail front elevation of the spring which partially encircles the front end of the weight. Fig. 23 is an underneath plan o'f'tiie magazine cover-plate and showing its adaptation for use as a screw-driver and as a spanner in assembling the parts. Figs. 24, 25, 26, and 27 are details of a screw-threaded bushing in the rear end of the bolt, Fig. 24 being a rear end elevation. Fig. 25 being a righthand side elevation, Fig. 26 being a front end elevation, and Fig. 27 being a left-hand side elevation, the expressions right hand and left hand meaning whcnthe gun is in position for'firing. Figs. 28, 29, 31), and 31 are details of a screw-threaded collar which encircles the rear end of the weight, Fig. 28 being a rear end elevation, Fig. 29 a right-hand side elevation, Fig. 30 a front end elevation, and Fig. 31 a left-hand side elevation. Figs. 32, 33, and 34 are details of the disk which covers the rear end of the collar on the weight and of the key formed thereon which locks the collar and weight together. Figs. 35 and 36 are details of a dust-plate which is fast to the collar shown in Fig. 28 and which is held in position by the disk shown in Fig. 32. Fig. 37 is a right-hand side elevation of the bolt, partly in section and with the extractor in place on the front end thereof. Fig. 38 is a front elevation of Fig. 37. Fig. 38 is a cross-section on line 38 38 of Fig. 38. Fig. 38 is a detail longitudinal section through the extractor, showing its engagement with the bolt and showing the stop-pin which limits its movement; Figs. 39, 40, 41, and 42 are details of the trigger, Fig. 39 being a plan, Fig. 40 a right-hand side elevation, Fig. 41 a front elevation, and Fig. 42 a lefthand side elevation. Figs. 43 and 44 are a right-hand elevation and a front elevation of a hook or .pawl which is pivoted on the trigger. Figs. 45 and 46 are a plan and righthnnd side elevation of a spring having on it a cam which the trigger encounters and which also locks the magazine-cover in place. Figs. 47, 48, and 4'3 are detail views of the rear member of the compound sear. Figs. 50 and 51 are details of the front member of the compound sear, the rear member being pivoted to and having a sliding movement on the front member when they are assembled. Fig. 52 is a perspective view of the trigger enlarger]. Fig. 53 is a perspective View of the rear member of the sear enlarged. Fig. 54 is a modification of the front part of the bolt and the parts therein. views showing another form of plunger, cartridge, bolt, and weight and are the preferred forms, Fig. 55 showing the parts in the positiori before firing, and Fig. 56 showing them just after the explosion, with the plunger driven back and just as the weight is about to separate from the plunger.

Referring now to the drawings, 1 is the breech portion of the gun-stock, and 2 is the receiver, which will be hereinafter called the .1 framefwhich supports and guides the bolt 2, and which supports the air-cylinder 4. The barrel 5 is screwed into the forward end'of the frame 2, and within the stock, on the under side of the frame, is secured the magazine 6. in the rear part of the air-cylinder 4 there may be a spring 135, which aids in driving the weight and bolt forward.

Projecting laterally from the bolt 3, at the forward end thereof, is a lever 7, w hich serves both as a. means to turn the bolt and to lock the bolt when it engages with the notch 8 in the frame 2. (Sec Figs. 1, 2, 17, 18, 3?, and 38.) Projecting laterally near the forward end of the bolt, from both sides of that portion of the bolt which is at the bottom when the bolt is unlocked, are lugs or short flanges 9 10, (see Figs. 17 and 38,) which when the bolt is in the unlocked positionare in salinement with longitudinal grooves 11 11 in the inm-r sides of the frame. .(See Figs. 1 and 3.) Said grooves form guideways for the flanges 9 11) when the bolt moves back and forward and prevent turning of the-bolt except when the lever 7 is opposite the notch 8. Formed in the inside of the frame is a recess 67 for the flange 10 to permit turning of the bolt in locking and unlocking. (See Fig. 17.) The frame 2 has a longitudinal slot- 12 through one side, through which the lever 7 extends to permit reciprocation of the bolt. For convenience of operating the lever 7 by hand it is preferably provided with a handle 1".

Projecting from the side of the bolt, near the forward end thereof, on the opposite side from the lever T, is :2. lug 14, which when the bolt slides backward and forward movesin aguidc- Figs. 55 and 56 are groove 158 in the side of the frame, which is in alinement with groove 15 in the air-cylinder. (See Figs. 3, 4:, 5, 7, 16, 17 18, and 38.)

Formed in the side of the frame isa recess 68 to receive the lug 14 when the bolt is locked and to permit the bolt to be turned to lock and unlock it. To completely unlock the bolt, the lever 7 has to be turned up .out of the notch 8 and through the inclined way 16. (See Fig. 2.) In the rear end of the boltthcre is formed a female screw-thread, into which is screwed a bushing 17, the inner end of said bushing butting against a spring 19. (See Figs. 24 to 27 and Fig. 3?.) The wall of the bushing is suliicicntly thick so that the internal diameter of the bushing is less than the diameter. of the bolt, and its end formsa butt for the spring 19. The interior diameter of the bushing affords a close sliding lit for the weight 21. There is suflicient looseness or clearance between the maleand female threads to allow a slight longitudinal movement of tho bushing and bolt relative to each other. The

purpose of this longitudinal movement is to cushion the blow of the boltngainst the weight, through the medium of the bushing, at the end of the rearward movement of the bolt. Inside of the bolt there is a still spring in, .the outer end of which butts up against the inner end of the bushing 17 and the innerend of which butts against a shoulder 20 on the bolt, said shoulder "being formed by reducing the internal diameter of the bolt. The weight 21 is slidablo within the bolt and is formed with two lugs 22 projecting laterally near its forward end.

Projecting inwardly from the intcriorof the bolt, on opposite sides thereof, and ex tend- IOC ing forwardly from the shoulder 20 are two spiral cams 23, with which the lugs 22 on the weight engage when, the weight moves rearward. the face 2-1 of each lug which engages with the spiral being inclined in such manner that the continued movement of the weight causes the bolt to turn on its axis, the weight being prevented from rotation, as will be hereinafter described. This turning is sufii cient to lift the lever? up out of the notch as far as the inclined faces thereof. The baclo' ward pressure after the explosion will cause the lever 7 after reaching the short incline or beveled corner 25 at the left side of the entrance to the notch as viewed in Fig. 2 to ride on said beveled edge entirely out of the notch, at which time the flanges 9 10 on the 'bolt will be in alinement with the grooves 11 in the frame, and the bolt will then be in position to slide straight rearward. Elie inclined, face 26 on the upper right-hand side of the notch 8 engages the lever T in the forward movement to start the lever down intothe .notch 8. The reason for giving to the belt a slight rearward movement longitudinally before it entirely turns outof the notch and for giving it a slight turning on the forward 'boss 155, Fig. 28, which slides mormnent before it enters the square part-of l the notch will he hereinafter explained.

In the form shown in F1gs. 1 to 54 the forward end of the weight 21 has a nose 2-l3,\vhich enters a recess 153 in the head of the bolt.

There is a passage en ti rely through the head of the bolt, within which is a plunger 27, said plunger being formed with an intermediate boss 28, the said passage being enlarged to form a chamber 29 for said boss 28. Said chamber .is long enough to allow a certain amount of reciprocation to the plunger. A bushing 30 is screwed into the forward end of the bolt after the plunger is inserted to secure the plunger. The plunger when in its forward position, as shown in Fig. 4, projects beyond the end of the bushing 30 into the cylindrical recess in the head 31 of the cartridge and rests against the primer 32. The invention is not limited to the use of a cartridge of the particular form shown. In the form shown between Figs. 4 and 54 in the drawings the head 31 is formed with a recess 151 to receive the primer 32 and of sufficient depth for the plunger 27 to enter said recess. The rear end of the plungeris seated in aslot 34 in the nose of the weight 21. The plunger may be detachably secured to the nose 33 of the weight, as by means of a C-shaped spring 35, (see Fig. 22,) which partially encircles the nose 33 and has a lug 36,.which passes through a hole 37 in the nose (see Fig. 21) and enters a slot or an annular groove 38 in the plunger. A groove is preferable to a slot in the plunger, so that it will fit if the plunger is slightly turned on its axis. The Weight extends rearwardly through the bolt and through the spring 19 and bushing 17. Its rear end is provided with a tubular extension piece or collar 39, which is screwed onto it or otherwise made fast to it, thus making it a part of the weight. The rear portion 40 of this collar is made of greater external diameter than the threaded portion, which screws onto the weight and forms ashoulder 41. (See Figs. 29 and 31.) Formed on the side of the extension 40 is a in a guidegroove 15 in the side of the air-cylinder 4 and prevents the weight from turning on its axis. (See Fig. 4.) Formed in the outside of this thickened rear portion 40 and extending rearward from the said shoulder 41 are cam-slots 42 43 opposite to each other, both having inclined sides. (See Figs 29 to 31.)

Formed on the bushing 17 back of the threaded portion is an annular flange 44, and extending rearwardly therefrom are two segmental cam-fingers 45 46, diametrically opposite each other, one of which, 45, has two inclined faces of unequal length and a squared end which corresponds with the inclined faces and the end'of the slot 42 in the collar 39. and

46, has a squared end 47 and corresponding with the slot said collar, so that when the said the other finger, one inclined face 43 in the lingers are brought into alinement with said slots and they are brought together the lingers will h't into the said slots. VVheu they are turned with relation to each other, so that the squared ends of the said fingers butt against the shoulder 41 on the collar, the lingers cannot enter the said slots and the tclescoping action cannot be completed.

The firing-pin 48 is formed with an enlarged rear portion 49, which is bored to receive the spring 50, which actuates the tiring-pin to discharge the cartridge. The engagement of said enlarged portion 49 with the forward end of the chamber limits the forward movement of the firing-pin relatively to the weight. Projecting downward from the said enlarged butt or rear end 49 at right anglesthereto is a lug 51, which is engaged by the sear, as will be hereinafter described. (Sec Figs. 10 and 11.) This lug 51 is formed with the lower part 52 of its front face at right angles with the tiring-pin to prevent the sear from becoming disengaged until the trigger is pulled. The firing-pin passe's lengthwise through a central hole in the weight and is central with the plunger 27. Preferably the forward part of thefiring-pin is reduced in diameter and passes through a central hole 54 in the plun ger to engage the primal-0Lth fleartridger The hole in the rear part of the weight is enlarged to form a chamber 55 large enough to receive the butt-end 49 of the firing-pin. Also the collar 39 has a hole 62 through it to receive the butt-end of the firing-pin and a slot 64 through the side of the said collar for passage of they lug 51 on the firing-pin. (See Figs. 28 to 30.) i

The rear end of the collar 39 is covered by a disk 56, having a pin 57, which projects at right angles to the face of the disk and is eccentric thereto. side wall of said collar 39 and passes through into a recess 156 in the threaded end of the weight 21. (See Figs. 4 and 19.) The said pin is keyed in the slot in the following manner: Projecting from theupper side of the pin 57 is a lug 59. The hole 58 is formed with a longitudinal groove on the left-hand side looking to the front. (See Fig. 28.) This groove'extends in far enough to allow the pin 57 to be pushed in its full length. Extending at right angles to the groove 60 is an annular groove 61, so that by turning the disk after the pin has been pushed in its full length the lug 59 will enter the annular groove 61, and thus prevent the withdrawal of the pin. The groove 60 is formed in the left side of the hole 58, so that to insert the pin it has to be started with the lug in alinement with said groove 60, and when the disk is turned to bring the lug into the annular groove 61 it will then come down into its correct position, with the lug 59 on the upper side.

The rear end of the firing-pin spring 50 is seated in a socket63 in the front face of the .105 It enters a hole 58 in the,

' (l isk 56.

The bamw'ay 73 h;

in Figs; Ta'nd' 3 l.e -l'soxthat A exerted in 'ndirectionto.

' bolt the beveled edge In order to allow for the turning of the disk to bring the lug into the annular groove 61, the socket 623 is made curred, as shown in Figs. 32 and 34.

A dust-plate (see Figs. 35 and 36) is rloretailed in the; slot ($6 in the side of the collar 39 (see Figs. 28 end 29) and extends alongment of the weight. (See Fig. 7.) Groove 157 i'uthe air-cylinder is in alinement with groove 12 in the frame.

In order to prevent the bushing 17 from working off orturning on the bolt it is keyed to the bolt in the following manner (see Figs. 7, 25, 2?, nnd 37c) Formed in the inside of the threaded end of the bolt is a groove or splinewny 69, and formed in the side of the bushing 17 is a similar groove or splinewey 70, said groove being on theoutside of the threaded end of said bushing, thence extending through a hole in the flange 44, and thence in the form of a. groove on the inside of the finger 46. Inserted into said keywny is a. key 71; consisting of a plate-spring formed with a hook 72 at the rear end, which when the weight and bolt are telescoped together, as in Fig. 7. engages in the grooved camwey 73 in the collar 39 on the same side as the slot 43. A portion of said camwey 7 3 extends diagonally crosswise of. the bottom of said slot 43 (see Fig. 31) and suddenly deepens at its rear end to receive the hook 22,'and thus prevent the camway from retraversingthe hook, which might otherwise lie-occasioned by the compression of the firing-pin spring. The hole 7 4 through the finger 46. (see Figs. 7 and 27,) which in Fig. TjS justover the back of the hook 72. isin part for convenience of insert-: i ng n tool or 'thepoint of a. bullet in assem hling or seperatingflthe parts, also to form an' thespring to v 'n butment for. ,the 1 backend limit. the longitudinal njient of thekoy 71 relatirely wet-3t an said finger lobe =b oetlaecollr 39 0f the weight awayfro n'th'e". fishing 1? :ofqthe u iierniitthe hook to draw out or the caniway ofhthe operation. The entrance to the corn way 73 is circumferential. as showniin; Fig: 31.

are brought together ageirnsuch movement will occur when they are turned in the position that they occupy when the bolt is unlocked, and the hook of the key will first en i a biitt;lie" sprinTg-letch key 71 will serve to hold them together, exceed when considerable forceiis applied'l D separatethem. as will be the caise doring'a certain imi-tfl when in the operation of the 'g'utiftb? weight and bolt after having been sepereted' gage the beveled edge 7:) on the end of the collar 39, as shown in Fig. 31, at a point near the under side as the said collar is shown in said Fig. 31. Said hevelolcdge will allow the hook to ride up onto the side or the collar until it comes opposite the entrance to said enmway '1'3. This will be the position it will hecupy until in the forward movementof the bolt the lever 7 reaches the diagonal portion of the notch 8. l Vhen the lever 7 moves down through the diagonal portion of the notch, it will turn the bolt enough for the hook 72 to pass through the circumferential portion of thecamwey 73, and when the bolt turns still farther, carrying the lever 7 down into the bottom of the notch 8, thehook 72 will travel through the diagonal portion of the cemwey 73. .W'hen the weight is forced rearward from the bolt, the beveled'edge of the eemwey'ili throws up the hooked endofthe spl'ingoutof the camgroove 73 and throws the back of the hook higher up in the hole 74 andallow's the weight I free motion straight rent-word. During this operation the hook has a tendency to revolve the boltby'rasozi ofithechmwdy; but" there 'is much more resistance to the bolt, being turned. owing tothe backward pressure of the explosion on the forward endof it, than there is power to turn it; 'duto.tlie'stitfnessof the spring-key 71 and the angle ofthe caniway 73. i For detail viewsof the trigger see F igslliiil, '40, 41."2,en d 52: The hemlof the trigger v A comprises two cheek-pieces T6 77, united ,bjr a ,eross-piece78. The finger-piece 79'extends loo downwardly from ther'zheek niece 77 (that being the left-hand eheek 'piece looking to ward the berrel of the gin) hnd is formed with an ofiset 80', thus bringing the linger-hook 81 in a line central with'the twobhceic-pieces I05 :and in proper position for conveniently working-the trigger. The trigger is pivoted by a .pivot 83 (see Fig. 4) ton. block 82, which ex- (tends between the rear ends of. the cheekai fiieces 76 7 7, said block fitting a rectangular n recess in the frame; v Secured to the under side of the frame 2 is -bracket 84. between which and the under l w y v side of thecross-piece 1'8 of the trigger-hood lie the isforre' jsfl'ie triggenspring 85. hehliri position h n I 15 86 on the said hreeket and a boss 87 on saidcross-piece 78. Secured to the upper "sidefof the trigger-plate by a screw 154 is ejtwisbed springplate IQLlmving at the forward end a lug 102, which enters a. hole 103 12 'jhi'the magazine-cover 104 to help retain said cover in position. Toward its rearpart it is "formedwith an inclined shoulder l05,;which th'e triggerengages when it is pulled back to init's the trigger to he pulled farther book into the automatic position to be more fully do scribed hereinafter. On the forward end of the cheek-piece 77 of the trigger there is ,formed a shoulder 164, which when the trig 3 tlieseminnutornetie position and which per 5 -tongue'and the rear of the ,slot 110 to allow bar-l; of the linger-hook engages a lu; 165 on lluunder side of the frame. (See Fig. 2.) Said lug forms a pivoting-point for the trigger. so that the trigger will be pulled down at the rear end. thus pulling down the block 82 and further compressing the trigger-spring H5. (See Fig. 13*.) When the said block is i pulled down. the air-cylinder 4 can he slid i rearward and removed from the frame. It 5 lirst slides rearwardly far enough for the'forward end of the air-cylinder 4 to be clear of the frame. This motion will also disengage i the hook 166 on the lower side of the air-cyli inder from the notch 167. The air-cylinder can then be lifted straight off. Then the bolt and weight can be removed from the frame straight rearward. W'hen the frame 2 is removed from the stock, the bracket 8% can be swung left-handed, thus partially unscrewing it. causing it to drop the spring 85, and then the trigger and tumbler can be removed from the frame.

Mounted on a pivot 88 between the forward branches of thecheek-pieces 76 77 is a tumbler 89, having a book 90, which engages the sear, as will be hereinafter described. A spring 91 holds the hook of the tumbler in engagement with the sear, asshown in Fig. 4 and other similar sectional views, said spring being coiled around a hub 92, one end of the spring being engaged in a hole 93 in the face of the tumbler and the other end being secured in a" hole 94 in the. cheek-piece 76. A hook projection 95 on the tumbler engages a pin 96, which extends between cheek-pieces 76 and 77 and prevents the tumbler from turning rearwardly under pressure of the spring beyond the vertical position shown in Fig. 4 when the sear is moved out of engagement with the book 90 of the tumbler. The saidhook 90 is formed with a beveled upper edge 97. as shown in Fig. 43, the purpose of which will be explained hereinafter. The said book 90 has also a beveled or inclined face'98 on the inner side. which acts as a cam when it engages and passes over a beveled or camface 130 on the sear to throw the sear to one side when the trigger is pulled entirely back into the position for automatic tiring, as will he hereinafter explained.

The com pound sear is composed of two members 106 and 107, pivoted together by a vertical pivot 108, the rear arm or tongue 109 of the forward member 106 beinginserted in the slot 110 between the lips 111 and 112 of the rear member 107 and the pivot 108 passing through the holes 113 in the lips and through the elongated hole 119 in the tongue 109. there being suflicient play between the end of the gcr is pushed forward by placing the thumb l the member 107 to turn in a. horizontal direction on said' pivot with relation to the forward member 106. The hole 119in the tongue 109 is elongated, allowing the rear member 107 to be moved slightly rearward with relation to the forward member and to the lug on the firing-pin. as will be hereinafter explained. (See Fig. The length of the elongated slot 1 i9 limits the forward and rearward movement of said rear member 107. The forward member 106 is mounted on ahorizontal pivot 114, having bearings in the frame. As the vertical pivot 108 is not fixed, the entire compound sear may be rocked vertically on the horizontal pivot 114; but only the rear member 107 can turn in the horizontal direction on the vertical pivot. The under side of the frame is slotted to prevent the members of the sear to project upward. The forward arm 115 of the forward member of the sear is inclined upward with relation to the rear arm, so that when the sear as -a whole is in a horizontal position, as in Fig. 4, the arm 115 will project upward. There is a notch 117 in the side of the flange 44 of the bushing 17, (see Figs. 4, 24, and 26.) into which the end of said arm 115 may project while the bolt is locked to permit rocking of the sear to carry the rear memberdown out of engagement with the In}; on the firing-pin, as will .be hereinafter described Exwpt for said slot the sear could not be rocked. and therefore the -trigger could not be pulled. There is also another notch, 118, in said flange 454 to receive the end of said arm 115 and permit the sear to be rocked when the bolt is turned into its unlocked position, atwhicb time the notch'118 will be on the under side. The sear-spring 120 is setin a diagonal position, (see. Fig. 4,) one end resting against an inclined face in the recessedstock and the other end pressing against the inclined face'122 of the rear. member of the sear, (seeFig. 53,) thus pressing the sear both upwardly and-rearwardly and tending to keep the rear member as far back as the elongated slot will'permitwhen it is not pressed forward by a greater force and tending to keep TuO it up in position for engaging the lug on the trigger back the tumbler is pulled down, and

if the hook 90 is engaged with the said lug The rear member 107 of 126 the rear arm of the sear also will be pulled down out of engagement with the lug 51 of the firing-pin, leaving the firing-pin free to be thrown forward by its spring 50. When the firing-pin is thrown forward, the searspring 120 -will throw the rear member 107 of the sear backward, as allowed by the elongated slot119, and upward, as allowed by the rocking of the entire sear on the horizontal edge 129 of the scar-lug 126, ing on its pivot suiliciently to turn the scar 129 of the lug 1913 is beveled. so that when i the trigger is released after being pulled hack the triggcnspring is strong enough to overcome the spring 91 and mnkethc beveled edge 97 of the hook to ride up ovei the beveled the tumbler turnfor that purpose. and then the spring 91 will snap the book 90 back into the upper side of the lug 126.

Projectinglaterally toward the scar from the upper end or hook part of the tumbler 89 is a bevel or cam faced lug 98. and projecting laterally from the adjacent side of the sear member 107 is a bevel or cam faced lug 130 lower down on the sear than is the lug 126. After the sear has become disengaged from the tiring-pin by the downward pull of the hook (which is accomplished by the half back pull of the trigger) and the sear has also become disengaged from the book by the backward thrust of the spring 91. if the trigger he pulled still farther back the cam-face 98 on the hook will ride down on the cam-face l3U on theisear and turn the sear member 107 on its vertical pivot 108. This lateral movement of the sear member 107 is notsuificient to carry it entirely out of the path of the lug 51 on the firing-pin; but itwill be also in the path of an inclined cam-face 134 in the weight extension-collar 39 for a purpose to-be hereinaftcr described. The upper side of the for ward part of check 77 of the trigger has a beveled inner edge 132, and the lower edge 131011 the adjacent side of the sear member 107 is also beveled off to avoid obstruction when the sear 107 is pushed to one side, as described, and also to return the sear into the semi-automatic position when the trigger is released. (See Figs. 39, 49, 53. and 54.)

The slot 64 in the under side of the weight extension-collar 39, through which thefiringpin lug 51 projects, is broadened out in the lower part thereof on the left-hand side facing the front (see Figs. .28 to 31) and extends from the front end rcarwurdly as far as the deeper portion of the slot in which lhe firing-pin lug moves. .The upper side of this broadened nnd extended portion 133 of the slot downward slope 134 toward the'rear. hen the sear member 107 is turned to one side by the full back pull of the trigger, as described, it will be in line with this slot 133. and if they are in this position when the weight 21 and bolt 3 are thrown forward the square end 52 of the firing-pin lug will first engage the scar and stop the tiring-pin without stopping the weight or bolt. The continued onward movement of the weight causes the inclined upper 5 face 134 of said slotto engage the said sear,

has a' on the bolt, thus turning up and as ii ridw uHI' it will push the-scar down out of cngugcnu-ul wiih the firing-pin lug. 'llnmin'zu'd morcnu'nt of the weight while. tlll' firing-pin is at rest will compress the liring-pin spring 50, so that by the time the sear is depressed suliicicntly to release the firingpin thospring Fill will he sniiiciently compressed to throw the firing-pin forward with full force to ignite the primer.

'lhe cartridges 136 are placed in the magnzine 6 by means of a clip (not shown) in the manner well known. The spring 13? brings one cartridge at a time into the position shown in Fig. 16, where its head will he en aged by the bolt in its forward move-mentand pushed into the explosion-chamber. The bottom of the inside of the frame 2 is formed with an inclined way 138, leading from the magazine, so that when the cartridge is pushed forward by the bolt the rounded end of the projectile in the cartridge will engage the incline and ride up into the chamber. The passage is made tapering, as shown in Fig. 5, so that but one cartridge at a time can be taken from the magazine.

The extractor is mounted on the side of the lever 7 in such manner as to be in position to engage in the circumferential groove 139 in the shell whatever may be the position of the lever 7. (See Figs. 38, 38", and 38".) The extractor consists of a bent plateor blade 149mm:- inga. curved edge 141 tofitin the grooro139 of the shell and havinga-shanlr tends up alongside of the lever 7. A lug 143 projects from the shank 142 through an elon gated slot 144 in the side of the lever. The lever 7 is hollow 'and contains a spring 145, which is seated on said lug and exerts a yield ing downward pressure on the extractor. When the cartridge is shoved into the chamher, the extractor engageswith yielding pres sure in the groove 13% on the shell. (See Figs. 7 and 12.) In order to prevent the can tractor from being lifted out of the circumferential groove 162 near the front end of the bolt, 9. pin 163 passes down through the spiral spring 145 and through the lug 143'. It is formed with a. shonidiar suliieiently far above the log to limit the sliding movement of the extractor.

Pivoted in the frame at 146 behind the magazine is the ejector 147. (See Figs. 2, 5, and 16.) The rear arm 184 of the ejector is outside of the path of the body of the bolt, but lies in the path of the lug 10. The forward arm 147 is in the path of the body of the bolt and is not engaged by the lug 10. (See Fig. 5.) When the boltis thrown back after a. discharge, it is engaged on its reararm 184 by the log 10 the front end into the position shown in Figs. 2 and 16 to engage the shell when driven back and to eject it. Nhen the forward end of the ejector is turned H2, which exup, it enters a slot 187 in the lower sideand to interfere with the 1110\01110111 of the bolt. l he sutlicient to straighten out the flange 18") and drlve the piston rearward.

'hen the bolt moves forward aga it Will engage and ride over the inclined back of the turned-up forwardarm of the ejector and turn it down again out of the path of the bolt and i hold it down until the bolt 15 again lorced rearward.

in the modification shown in Fig. 54 the pl unger 27 is made without any perforation for the passage of the firing-pin. Instead of having the end of the firing-pin come in direct contact with the primer it strikes the rear end of the plunger in the forward movement and drives the plunger forward the plunger being formed with a reduced end or boss 150, which strikes and explodes the primer.

In Figs. and 56 are shown the preferred form of cartridge, which is somewhat different from that shown in the other figures, and also a somewhat different form of weight and bolt which are adapted for use with the cartridge.

' The primer 170 is held in a cupped-out plug or piston 171. which is in the recess 172 in the head of the cartridge 173., and which extends back flush with the rear end of the cartridgehead 174 before the ignition and is driven rearwardly by the explosion, so that when it drives the plunger 175 rearward the forward end of the plunger will be driven back inside of the bolt 176 and the piston 171 will follow the plunger and project inside of the bolt. while in the form shown in Figs. 4 and 54 before ignition the primer is in the bottom of the recess 151 in the head of the cartridge and the plunger 27 extends into said recess, and when the cartridge is exploded the rearward movement of the plunger is limited by the lug 28. so that when in its most rearward position, as shown in Fig. 12, the forward end of the plunger is flush with the end of the bolt and the rear end of the primer is flush with the end of the cartridge-shell. shown in Figs. 55 and 56 the plunger 175 is formed with a shoulder 177, which engages with the shoulder-181 on the bolt to limit the rearward movement; but instead of being reduced again at its forward end. as in Fig. 4, so as to enter the recess in the head of the cartridge. the full breadth of the plunger extends to the forward end and covers the end of the recess 172 in the cartridge. The screw-bushing 30 of Figs. 4 and 54 is omitted, and there is no need for the spring-clamp 36 for connect-4 When the cartridge is exploded, the force will In the form The operation of the lirearm is as follows: Assume that the magazine is empty and the bolt is locked. as shown in Figs. 1 and 4. and no cartridge in the chamber. although one is shown in the chamber in Fig. 1. To lill the magazine. the bolt is unlocked by gras ring the handle 13 with the handand turning the lever 7 up out of the notch 8 and through the inclined pdrtion 16, then pulling the leverhack as far as it will go. carrying the bolt. weight. and firing-pin. and compressing the spring 135. The bolt as it slides rearward will engage with and ride over the inclined front face 127 of the sear member 107 and push itdown. rocking the entire scar on the horizontal pivot 114. The bolt will be held in this position by the end 185 of the carrier 186 until the clip which holds the cartridges is inserted. Then the clip will hold the bolt back until the clip is pulled out, leaving the cartridges in the magazine. The bolt is then pushed forward and the lever 7 is turned down again into locking position. As the bolt moves forward its front end engages the rear end of the uppermost cartridge in the magazine and shoves it into the chamber of the barrel. the flange of the extractor 110 engaging in the groove of the cartridge, as already described. This will bring the parts into the position shown in Fig. 4, the gun n'ow being ready for firing, the hook 90 of the tumbler-resting on the upper side of the lug 126 of the scar 107 and the firing-pin spring 50 compressed. As already stated, one cartridge only may be fired at each pull of the trigger, or all in the magazine maybe fired by'a single pull. according to the extent it is pulled. For convenience of designation the former is termed the semi-automatic and the latter is termed the automaticfiring. In the semi-automatic operation by pulling the trigger part way back one cartridge is fired, the shell ejected. and another cartridge is pushed into the chamber; but another cartridge will not be fired until the trigger is released and again pulled. In the automatic operation by pulling the trigger fullback the firing-pin is automatically released and thrown forward simultaneously with the locking of the bolt, when the bolt moves forward and inserts the second cartridge after the first cartridge has been fired. The semi-automatic operation will he first described. The trigger is pulled back until it encounters the foot of the incline 105 I 

